FIELD: oil and gas production.
SUBSTANCE: procedure performed in well consists in lowering engine into well, in actuating engine for rotation of bore bit and in implementing engine for pumping well fluid medium from well. The well unit consists of a tubular element, of a shaft installed in the tubular element, of the first drive designed to rotate the shaft, in response to medium, passing through the tubular element from surface of the well, in the drilling engine mode, and of the second drive designed to rotate the shaft to pump well fluid medium from the well to surface in the pump mode. The well system consists of a string, of an isolating device selectively actuating the bore bit for isolating circular space outside the string and of unit in the first mode of unit operation rotating the bore bit and in the second mode of the unit pumping well fluid medium from the well to surface of the well.
EFFECT: reduced amount of round-trips used for well completion.
21 cl, 12 dwg
